The burst search in LIGO relies on coincident detection in multiple interferometers. As no assumption is made about the event waveform or duration, the analysis pipeline requires loose coincidence in time, frequency and amplitude. Confidence in the resulting events and their waveform consistency is established through a time-domain coherent analysis: the "r-statistic test". This talk presents a performance study of the post-coincidence steps applied to low-threshold/high-false-rate background events from the LIGO S2 playground dataset. Particular emphasis will be given to the r-statistic test, its ability to suppress the background false rate, and its efficiency at detecting simulated bursts of different waveforms close to the S2 sensitivity curve.